In anticipation of his incredibly comprehensive new cookbook, The Food Lab's J. Kenji López-Alt debunked the most common cooking myths for us.

J. Kenji López-Alt is not messing around when he says he's cooked over 1,000 steaks and baked more than 1,500 chocolate chip cookies. His recipes, which find a happy home and cult following at The Food Lab on Serious Eats, undergo rigorous scientific testing: Each trial tweaks one specific variable until the finished product is juuuust right. He's demystified everything from deep-frying chicken and making the fluffiest pancakes to sous-viding steak and building a Whopper-style burger—and now he's publishing The Food Lab: Better Home Cooking Through Science, a 1,000-page cookbook (more of a textbook or essential encyclopedia, really) packed with everything he knows. Kenji shared a few crucial tips.

Assume Nothing

The goal of The Food Lab is to help people become better cooks, he explains. The first thing to remember? Never take anything for granted. Never just take someone's word for it. "Trust evidence, not anecdotes," he says.

To Kenji, the science of food has nothing to do with chemicals or modernist cuisine. Rather, "Science is a method of understanding the world around you. It's about understanding—on a basic chemical, thermodynamic level—what's happening in your food." To demonstrate, he shared six rules of cooking he's debunked with experiments over the years.

Photo by Alex Lau

Scrambled Eggs. Photo: Alex Lau

Six Common Cooking Myths, Debunked

1. Use a Lot of Water When You Boil Pasta"Traditionally, people say to use a lot of water, because you want it at a rolling boil so that the water can come back up to boil as quickly as possible after you add the pasta in," he says. While that sort of makes sense, it's not actually true. "If you do a very simple test at home, and get a pot with a quart of water, and another with a gallon of water, and put them side-by-side, the one in the smaller pot will return to a boil faster," he explains. Why? Because no matter how much water you have, "Both pots need to regain the same amount of energy to return to a boil, but the bigger pot of water is losing energy faster to the environment than the smaller pot."

2. Searing a Steak From the Start Locks in Its Juices"If you cook two steaks side-by-side, one seared at the beginning or one seared at the end, you'll see that the one seared at the end will lose fewer juices. If you start it cool in the oven and then sear it at the end, it cooks much more evenly with edge-to-edge color," he explains.

3. Don't Puncture a Steak with a Fork, Because You'll Lose JuicesUsing a fork to flip your steaks is actually completely okay. "A steak is not a water balloon," notes Kenji. "It's more like a series of tiny water balloons." That is, if you stick your fork in it, you might puncture one or two, but it's not like you've opened the floodgates. Again, Kenji recommends seeing for yourself in a side-by-side test.

4. Don't Salt Your Eggs While You're Scrambling ThemThe myth says that adding salt to eggs while you're scrambling or making an omelet will make the eggs tough. Kenji says otherwise: "After a lot of testing, that's not the case. If you let your eggs rest with some salt for 15 minutes, they'll actually retain more moisture. That's because the salt breaks down some of the proteins and that forms a net that holds in more moisture as the eggs cook."

5. Add Vinegar to the Water When You Hard-Boil Eggs so the Shells Will Peel More EasilyIgnore theories that the only easy-peel hard-boiled eggs are old eggs, salted water, vinegar-ed water, or poking a hole in the end. While old eggs do peel better than fresh eggs, given the same starting egg, starting in boiling water will help it peel better. "I actually did an experiment. I cooked several hundred eggs and had some people peel them without knowing how I cooked them. I counted the number of defects in the surface of the eggs and found that the number one thing that makes your eggs easy to peel is the starting temperature of the water," he explains. That is, the hotter the water is when you start boiling your eggs, the easier they are to peel.

6. Don't Salt Your Beans While They're CookingPeople say don't salt your beans while you're cooking them; salt at the end, otherwise they'll become tough. "That's almost the opposite," says Kenji. "Salting your beans will actually keep things intact as they cook." In fact, there's only one thing you shouldn't do to your beans as they cook: add vinegar. Acid can inhibit the breakdown of pectin.

"A lot of it comes down to preference," Kenji levels. But getting scientific with common techniques or cooking questions can build up to a great recipe. Which is the whole point, he says. Because, "If I'm going to make a hamburger, I want it to be the best it can be."